EP0667848B1 - Procede de production d'isophorone - Google Patents

Procede de production d'isophorone Download PDF

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Publication number
EP0667848B1
EP0667848B1 EP94927936A EP94927936A EP0667848B1 EP 0667848 B1 EP0667848 B1 EP 0667848B1 EP 94927936 A EP94927936 A EP 94927936A EP 94927936 A EP94927936 A EP 94927936A EP 0667848 B1 EP0667848 B1 EP 0667848B1
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EP
European Patent Office
Prior art keywords
isophorone
kpa
mmhg
acetone
distillation column
Prior art date
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Expired - Lifetime
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EP94927936A
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German (de)
English (en)
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EP0667848A1 (fr
EP0667848A4 (fr
Inventor
Michael C. Grebinoski
Donald Glassman
Carole L. Elias
Alain A. Schutz
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Braskem America Inc
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Aristech Chemical Corp
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
    • C07C45/61—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups
    • C07C45/67—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton
    • C07C45/68—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms
    • C07C45/72—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms by reaction of compounds containing >C = O groups with the same or other compounds containing >C = O groups
    • C07C45/74—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by reactions not involving the formation of >C = O groups by isomerisation; by change of size of the carbon skeleton by increase in the number of carbon atoms by reaction of compounds containing >C = O groups with the same or other compounds containing >C = O groups combined with dehydration

Definitions

  • This invention relates to the manufacture of isophorone from acetone.
  • This invention is designed to employ effectively a catalyst of the type described by Schutz in U.S. Patent 4,970,191; preferably the catalyst is enhanced by the process of extruding or otherwise forming it described by Schutz and Cullo in U.S. Patent 5,153,156.
  • Methods of making isophorone described by Schutz in U.S. Patent 5,055,620 and by Schutz and Cullo in U.S. Patent 5,202,496 are also especially applicable to the present invention; use of the catalyst to react acetone in the vapor phase is particularly of interest in the present invention.
  • the Schutz and Schutz/Cullo patents employ pseudoboehmite reacted with an acid to form a gel, to which is added magnesium oxide or hydroxide in particular ratios, followed by agitation, heating, and calcining. These patents are incorporated herein by reference in their entirety.
  • our invention may use also, or in place of the catalysts of the above-recited Schutz and Schutz/Cullo patents, a catalyst of the type disclosed by Reichle in U.S. Patents 4,165,339 and 4,458,026 and/or Papa et al U.S. Patent 4,535,187, to the extent they are practical.
  • this invention is a process for the vapor phase aldol condensation of acetone to make isophorone, and is intended to include the use of any catalyst which will catalyze such a reaction, including catalysts described in any of the above-cited patents which are known to do so, to the extent applicable.
  • This invention relates to a method of making isophorone, characterized by the steps of:
  • fresh acetone is mixed with the various process recycle streams consisting primarily of acetone, mesityloxide, and isophorone.
  • the resultant feed is partially vaporized preferably by heat exchange with the reactor outlet, then totally vaporized using steam or another suitable heating medium.
  • the thus obtained vapor is superheated preferably by further heat exchange with the reactor outlet, and finally brought to an inlet or feed temperature of 225-325°C in a direct fired heater or other suitable heat source.
  • the superheated feed is reacted in the vapor phase to convert about 10 to 35% of the acetone, causing an adiabatic temperature rise of about 7 to 50°C.
  • the reactor product is partially condensed, preferably by the aforementioned heat exchange with the reactor feed, thus recovering a large portion of the heat of reaction which, in the preferred version, in turn decreases the need for external energy sources.
  • Unreacted acetone is then separated from the reaction products by distillation and recycled to the reactor.
  • the bottoms product from the distillation column consists of an organic phase and an aqueous phase.
  • the two phases are fed to a decanter or other phase separator after cooling by interchange with the decanter organic outlet.
  • the organic phase is fed to another distillation column where the mesityloxide and remaining water are separated from the crude isophorone and then recycled to the reactor.
  • Beta isophorone is the isomer illustrated in a structural formula as follows:
  • beta isomer of isophorone (and phorone isomers) is generally less than about 10% of the alpha, at least under the conditions of our process, consistent removal of it has proven to be very beneficial to the color of the final product.
  • the crude isophorone from the bottoms of the beta isophorone/phorone distillation is further purified in a final distillation column to remove heavy components.
  • the resultant isophorone product has a purity of greater than 99%. Further improvement in the overall yield of the process can be realized by the optional stripping of the reaction water to recover acetone, mesityloxide, and isophorone to the extent that they are soluble in the reaction water.
  • the recovered organics from the overhead of the stripper can be recycled to the acetone column.
  • our process is seen to comprise feeding acetone in the vapor phase at a temperature between about 225-325°C to an aldol condensation catalyst to convert about 10% to about 35% of the acetone to a reaction product containing about 4% to about 20% alpha isophorone, removing water and mesityloxide from said reaction product, and, in a separate isomer distillation, removing the beta form of isphorone, and phorone, from said reaction product.
  • the isophorone product of >99% purity is recovered by removing the heavies in a final distillation step. Soluble acetone, mesityloxide, and isophorone may be recovered from the reaction water and recycled to the acetone column.
  • Figure 1 is a block flow diagram or flow sheet of our process.
  • Figure 2 is a block flow diagram of a pilot plant used to demonstrate the front end of the process.
  • Figure 3 is a block flow diagram of a pilot plant used to demonstrate the back end of our process.
  • feed mixer 1 continuously receives acetone from line 2, and mixes it with recycled materials in lines 3, and 4 to be described.
  • the mixture is heated, preferably by interchange 5 with the reactor outlet and directed to reactor 6 which is maintained initially at a temperature between 225-325°C and at a pressure to deploy the mixture in the vapor phase.
  • the reactor contains a catalyst of the type described in the previously-cited Schutz/Cullo patents, in an amount to convert about 10-35% of the acetone in the feed, which will tend to increase the temperature in the reactor by about 7-50°C.
  • the active portion of the catalyst is preferably a synthetic anionic clay of the type described in lines 33-38 of column 3 of U.S.
  • Patent 5,153,156 namely of the formula (Mg 1-x Al x )(OH) 2 .xA where x is a number from 0.1 to 0.5, A is a univalent organic anion of the formula RCOO - , where R is CnH 2n+1 and n is 0 to 4.
  • the reaction product (typically about 20% converted) is sent to the acetone distillation column 7 along with fresh acetone in line 8 and recovered organic feeds and products in line 20 to be described.
  • Column 7 is operated at a pressure of 300 mmHg to 20 psig, preferably about 650 mmHg to 850 mmHg.
  • the resultant stream is two phase and is preferably fed to decanter 10 whereby the isophorone-rich organic layer is separated from the aqueous phase which contains most of the water formed in the reaction.
  • the decanter feed is cooled by interchange with the decanter organic outlet in heat exchanger 9.
  • the two phases may be fed directly to the subsequent distillation; however, this will result in a large increase in energy requirements, thus reducing the overall energy efficiency of the process.
  • the decanted organic phase is then forwarded to the mesityloxide distillation column 12, where mesityloxide is removed for recycling through line 3 to feed mixer 1, and water is removed from the system in line 13.
  • Column 12 operates at a pressure of about 100 mmHg to 20 psig, preferably about 400 to 600 mmHg.
  • the reaction product continues to a beta distillation column 14, where beta isophorone and phorone isomers are removed for recycling through line 4 to feed mixer 1, and mesitylene and other light impurities are purged in line 15.
  • Column 14 operates at a pressure of 20 mmHg to 600 mmHg, preferably 100-300 mmHg (about 5 psig).
  • Column 16 operates at a pressure of 10 to 300 mmHg, preferably 50 to 100 mmHg (about 5 psig).
  • Water from line 11 and line 13 is sent to a stripping column 19, where organic components dissolved in the water are removed for recycling through line 20 to the acetone distillation column 7; waste water is removed in line 21.
  • the pilot plant of Figure 2 was set up so that the feed tank 22 could receive unused acetone from line 25, and distilled acetone from line 30, and/or recycled products such as mesityloxide and isophorone isomers from line 24.
  • the material contained in the feed tank 22 was pumped and vaporized through line 26 to the reactor 27 containing the catalyst, at a rate of about 665 g per hour.
  • the reactor temperature was maintained at about 270 to 300°C and the reactor pressure was about 15 psig.
  • the reactor outlet stream was condensed and stored in tank 28 and subsequently pumped to the continuous column 29, which was an Oldershaw with 20 rectification trays, 8 stripping trays, maintained at 760 mmHg and with a reboiler temperature of 95°C.
  • mesitylene tends to build up; after two weeks of recycling, its concentration increased from an initial 0.02 to 0.1 weight percent.
  • the process may be designed to purge the mesitylene, as in line 15 of Figure 1. It may be calculated from Table 2 that each 100 parts of acetone was converted to 70.85 parts alpha isophorone, 20.37 parts water, and 8.76 parts heavies.
  • the pilot plant of Figure 3 was set up to simulate the "back end" of the plant.
  • Column 35 representing the third stage column 16 in Figure 1, was a 1" Oldershaw having 20 stripping trays, 15 rectification trays, and operated at a top pressure of 70mmHg, and a reboiler temperature of 188°C.
  • the isophorone product was collected from line 42 and the heavies from line 39.
  • Mesityloxide from line 40 and isophorone isomers from line 41 were recycled to the reaction section, i.e. reactor 27 in Figure 2.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Hydrogenated Pyridines (AREA)
  • Nitrogen And Oxygen Or Sulfur-Condensed Heterocyclic Ring Systems (AREA)
  • Saccharide Compounds (AREA)

Claims (12)

  1. Procédé de préparation d'isophorone, caractérisé par les étapes selon lesquelles:
    (a) on effectue une condensation aldolique de l'acétone en phase vapeur en présence d'un catalyseur de condensation aldolique à une température comprise entre 225°C et 325°C pour obtenir un produit réactionnel dans lequel au moins 10 % de l'acétone est transformée;
    (b) on sépare l'acétone n'ayant pas réagi du produit réactionnel dans une colonne de distillation d'acétone, en obtenant ainsi un système à deux phases;
    (c) on sépare la phase aqueuse du système à deux phases dans un décanteur;
    (d) on sépare l'oxyde de mésityle et l'eau de la phase organique dudit système à deux phases dans une colonne de distillation de l'oxyde de mésityle;
    (e) on sépare la β-isophorone, les isomères de phorone, le mésitylène et d'autres impuretés légères du produit réactionnel dans une colonne de distillation de β-isophorone; et
    (f) on purifie le résidu de la colonne de distillation de β-isophorone dans une colonne de distillation du produit pour obtenir un produit final contenant au moins 99 % d'a-isophorone.
  2. Procédé selon la revendication 1, dans lequel, dans l'étape (e), on sépare la β-isophorone à un niveau intermédiaire de la colonne de distillation, et on évacue le mésitylène.
  3. Procédé selon la revendication 1, dans lequel la colonne de distillation d'acétone dans l'étape (b) fonctionne sous une pression de 40 kPa à 239 kPa (300 mm Hg à 20 psig).
  4. Procédé selon la revendication 1, dans lequel la colonne de distillation de l'oxyde de mésityle dans l'étape (d) fonctionne sous une pression de 13 kPa à 239 kPa (100 mm Hg à 20 psig).
  5. Procédé selon la revendication 1, dans lequel la colonne de distillation de la β-isophorone dans l'étape (e) fonctionne sous une pression de 2,7 kPa à 135 kPa (20 mm Hg à 5 psig).
  6. Procédé selon la revendication 1, dans lequel la colonne de distillation du produit dans l'étape de purification (f) fonctionne sous une pression de 1,3 kPa à 135 kPa (10 mm Hg à 5 psig).
  7. Procédé selon la revendication 1, dans lequel l'oxyde de mésityle séparé dans l'étape (d) est recyclé dans le réacteur.
  8. Procédé selon la revendication 1, dans lequel la β-isophorone séparée dans l'étape (e) est recyclée dans le réacteur.
  9. Procédé selon la revendication 3, dans lequel la pression est de 86,6 kPa à 113,3 kPa (650 mm Hg à 850 mm Hg).
  10. Procédé selon la revendication 4, dans lequel la pression est de 53,3 kPa à 80 kPa (400 mm Hg à 600 mm Hg).
  11. Procédé selon la revendication 5, dans lequel la pression est de 13,3 kPa à 40 kPa (100 mm Hg à 300 mm Hg).
  12. Procédé selon la revendication 6, dans lequel la pression est de 6,7 kPa à 13,3 kPa (50 mm Hg à 100 mm Hg).
EP94927936A 1993-09-09 1994-08-22 Procede de production d'isophorone Expired - Lifetime EP0667848B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US08/118,341 US5352839A (en) 1993-09-09 1993-09-09 Isophorone process
US118341 1993-09-09
PCT/US1994/009440 WO1995007255A1 (fr) 1993-09-09 1994-08-22 Procede de production d'isophorone

Publications (3)

Publication Number Publication Date
EP0667848A1 EP0667848A1 (fr) 1995-08-23
EP0667848A4 EP0667848A4 (fr) 1996-01-10
EP0667848B1 true EP0667848B1 (fr) 1998-12-09

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP94927936A Expired - Lifetime EP0667848B1 (fr) 1993-09-09 1994-08-22 Procede de production d'isophorone

Country Status (7)

Country Link
US (1) US5352839A (fr)
EP (1) EP0667848B1 (fr)
JP (1) JPH08503713A (fr)
AT (1) ATE174321T1 (fr)
CA (1) CA2148348C (fr)
DE (1) DE69415138T2 (fr)
WO (1) WO1995007255A1 (fr)

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5877354A (en) * 1997-12-03 1999-03-02 Aristech Chemical Corporation Process for making isophorone with improved color and color stability
CN101633610B (zh) * 2009-08-13 2012-10-17 浙江大学 一种α-异佛尔酮的制备方法
DE102010029272A1 (de) 2010-05-25 2011-12-01 Evonik Degussa Gmbh Verfahren zur elektrochemischen Herstellung von Isophoron
DE102010062603A1 (de) 2010-12-08 2012-06-14 Evonik Degussa Gmbh Verfahren zur Herstellung von 3-Aminomethyl-3,5,5-trimethylcyclohexylamin
DE102010062587A1 (de) 2010-12-08 2012-06-14 Evonik Degussa Gmbh Verfahren zur Herstellung von Isophoron
DE102011075777A1 (de) 2011-05-13 2012-11-15 Evonik Degussa Gmbh Verfahren zur Herstellung von Isophoron in Gegenwart mindestens eines Entschäumers in der Abwasserkolonne im Aufarbeitungsteil
CN103435461B (zh) * 2013-07-24 2015-06-03 河北工业大学 异佛尔酮的生产工艺
CN103467263B (zh) * 2013-09-13 2015-06-17 江苏焕鑫新材料股份有限公司 一种异佛尔酮的制备方法
CN108911956B (zh) * 2018-06-20 2021-10-08 江苏焕鑫新材料股份有限公司 一种裂解副产物在缩合反应中的提纯工艺

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL272258A (fr) * 1960-12-23
NL272976A (fr) * 1960-12-31
US3462348A (en) * 1968-03-25 1969-08-19 Exxon Research Engineering Co Purification of isophorone by plural stage distillation
GB1265029A (fr) * 1969-06-02 1972-03-01
GB1498017A (en) * 1974-05-15 1978-01-18 Bp Chem Int Ltd Isophorone production using a potassium hydroxide catalys
GB1528129A (en) * 1975-10-20 1978-10-11 Bp Chem Int Ltd Process for the production of isophorone
US4165339A (en) * 1976-02-12 1979-08-21 Union Carbide Corporation Catalytic aldol condensations
US4458026A (en) * 1982-06-02 1984-07-03 Union Carbide Corporation Catalysts for aldol condensations
US4434301A (en) * 1982-08-25 1984-02-28 Union Carbide Corporation Production of low color refined isophorone
US4535187A (en) * 1983-12-21 1985-08-13 Union Carbide Corporation Preparation of isophorone and mesityl oxide from acetone
US4970191A (en) * 1989-04-18 1990-11-13 Aristech Chemical Corporation Basic mixed oxide
US5153156A (en) * 1989-04-18 1992-10-06 Aristech Chemical Corporation Process for making efficient anionic clay catalyst, catalysts made thereby, and method of making isophorone
US5055620A (en) * 1989-04-18 1991-10-08 Aristech Chemical Corporation Process for aldol condensation

Also Published As

Publication number Publication date
JPH08503713A (ja) 1996-04-23
EP0667848A1 (fr) 1995-08-23
EP0667848A4 (fr) 1996-01-10
US5352839A (en) 1994-10-04
WO1995007255A1 (fr) 1995-03-16
ATE174321T1 (de) 1998-12-15
CA2148348C (fr) 2001-01-02
CA2148348A1 (fr) 1995-03-16
DE69415138D1 (de) 1999-01-21
DE69415138T2 (de) 1999-05-06

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